"I was freaked out because I know how bad it is to inhale it," she said.
Frechette and her partner arrived at the Winhall Brook Camping Area late one night in July. She woke up to cook breakfast around 8 a.m. the following morning. She started a fire, placed frozen bacon into a pan to defrost, and sat on a nearby picnic table as her partner remained asleep in the car.
She then saw a truck arrive at the campsite. Several men began operating what she said sounded and looked like leaf blowers emitting a mist into the air about 20 feet to 30 feet from the picnic table. Frechette asked one of the men what they spraying.
"Oh, it's just Roundup," she said one man replied.
She then asked the crew to stop spraying the herbicide. She said the men discussed her concerns and responded that it was their job to control invasive species in the campground. After notifying other campers about the herbicide application, she and her partner left the campsite.
Frechette last week filed a formal complaint with the state. Now, the Vermont Agency of Agriculture, which regulates the use of pesticides, says the herbicide applicator violated state regulations because there were unprotected visitors present at the campground during the time of the spraying.
The agency is still considering whether anyone was physically harmed and what enforcement action to take. Agriculture Secretary Chuck Ross would have to sign off any enforcement action. The campground incident is one of about one dozen cases of potential herbicide exposure the agency is currently investigating, an official said.
It remains unclear whether the state can take enforcement action against the U.S. Army Corps of Engineers, which manages the campground and contracted the herbicide applicators.
Cary Giguere is the agency's agrichemical program manager leading the investigation. He said the state requires pesticide applicators to follow label instructions. Pesticide is a broad terms that includes insecticides and herbicides.
"One of our catch phases in terms of training applicators is 'the label is the law,'" Giguere said.
According the agency, the herbicide applicators were spraying a blend of brand-name herbicides called Rodeo, Arsenal and Escort.
Each label states the product should not be applied in a way that will contact workers or other people, either directly or through drift, and only protected handlers may be in the area during the application.
Giguere said the area includes the entire campground. According to Frechette, there were other families and pets visiting the campground before she and her partner left.
The herbicides are often used to control the spread of invasive plants, including Japanese knotweed, an invasive perennial that looks like bamboo. The active ingredient in Rodeo is glyphosate; in Arsenal it's imazapyr; and in Escort it is metsulfuron methyl.
According to federal regulators, exposure symptoms include short-term health effects such as congestion, and eye, skin, nose and throat irritation. Long-term exposure to glyphosate includes kidney damage and reproductive health effects, according to the Environmental Protection Agency.
A week after leaving the campground, Frechette said she felt congested and dizzy, her eyes were watering, and she was coughing up yellow mucus. Within five days, she said her health returned to normal.
The state can take enforcement action ranging from a warning to revoking the applicators' state license, he said. The state can also request the company to pay penalties up to $5,000 for each violation.
The applicators, Vegetation Control Service Inc., a vegetation management company from Athol, Massachusetts, said in a letter to the agency that the company did not spray the site where Frechette was parked. It said after hearing from Frechette, the company encountered no other issues from visitors.
The campground is one of the Corps' six managed recreational areas. The well-manicured site includes a range of amenities: a parking area, flush toilets, drinking water, electric hookups, hot water, a playground, trails and access points to the West River for fishing and swimming.
Larry Rosenberg, a spokesmen for the U.S. Army Corps of Engineers, said the management of invasive species is part of a national program to protect the environment and manage the Corps' recreational areas.
Rosenberg said the Corps has strict application standards and takes complaints seriously. He said the Corps may apply pesticides on an annual basis, but less if the invasive plants are killed off.
Rosenberg said the Corps is not required to notify Vermont agencies of the herbicide application. However, after the complaint, he said the Corps will now notify the public of any scheduled herbicide applications, including through social media.
Giguere said the state does require a permit to control invasive species on private property. He said it is worth considering to ensure responsible invasive species control.
He said environmental groups and communities in Vermont have "waged a war" on controlling invasive species, even if it means tearing out buckthorn plants on private property. Nonetheless, he said in the past 15 years or so of controlling invasive plants, three complaints have been filed to the state.
Despite the incident with the herbicide applicators, Frechette said the campground was neatly manicured with pristine green grass.
"It's really pretty," she said. But she questioned the off-site impacts of the pesticide application, citing the miles of waist-high poison parsnip lining the roads from the campground to Jamaica.